Foregoing the click reflex, I am not so proud to say that Urosukidoji is technically a hentai. It's about a demon born from human flesh, and most of the story involves human women being raped by demonic entities. In fact, the Urotsukidoji, after awakening, uses his massive member (and ejaculate) to evaporate a nurse in a hospital.

Don't get me started on Urotsukidoji and tentacles. Too damn many, if you ask me (though they aren't tentacles so much as they're extremely long tongues and prehensile demon wing-wong). That, and Wicked City has a bunch.